Automatic speed-ratio regulator for hydraulic couplings and changespeed gears



Feb 12, 192., I 1,701,903

. s a, wmsqws'r AUTOHATIC SIEED RATm REGULATOR FOE. HYDRAULIC COUPLINGSAND CHANGE SPEED'GEAHS Filed July l'T; 1922 8 ShBB'bS-Shfiflt 1 INVENTOR[W 7744z 4 y Attorneys,

Feb 12, 1929,

s. G. WmGQmsT AUTOMATIC SPEED RATIO REGULATOR FOR HYDRAULIC COUPLINGSAND CHANGE SPEED GEARS Filed July 17. 1922 3 Shets-Shmi; 2

, INVENTOR Q aka/am 0 1 WWW 5;- G. WHNGQUIST AUTOMATIC SPEED RATIOREGULATOR FOR HYDRAULIC COUPLINGS AND CHANGE SPEED GEARS Filed July m,1922 s sheets s'iieet 3 Feb. 12, 1929,, 1JOL903 AUTOMATIC SPEED RATIOREGULATORFOR HYDRAULIC COUPLINGS AND CHANGE SPEED GEARS Filed July 17.1922 a Sheets-Sheet 4 Fla 4 1/ a 45 I g jmfmim" JZWW flw'ym eh. E2,1929:

s. G. wmcaQulsT FOR HYDR p GEARS 19 AUTOMATIC SPEED RATIO REGULA ANDCHANGE s Filed Jul,

AUTOMATIC SPEED RATIO REGULATOR FOR HYDRAULIC COUPLINGS S. G. WINGQUISTFeb 12 AND CHANGE SPEED GEARS Filed July 1'7. 1922 8 Sheets-Sheet 6 Feb.12, 1929. 1,7m,903

' S. G. WINGQUIST AUTOMATIC SPEED RATIO REGULATOR FQR HYDRAULICCOUPLINGS AND CHANGE SPEED emng Filed July 3.7. v1.922 8 Sheets-finest'7 Feb, 1, 1929. 1,701,903

v 5. G. WIINGQUIST I AUTOMATIC SPEED RATIO REGULATOR. FDR HYDRAULICCOUPLINGS AND CHANGE SPEED GEARS Filed July 17. 1922 8 sheets-sheet s I17 51 18 I Z? Patented Feb. 12, 1929.

1,101,903 PATIENT OFFICE.

UNITED STATES SVEN GUSTAF WINGQUIST,

or eo'r'rnnnone, SWEDEN.

AUTOMATIC SPEED-RATIO REGULATOR FOR HYDRAULIO COUPLINGS AND CHANGE-SPEEID GEARS.

Application filed July 17, 1922. Serial No.

This invention relates to automatic means for controlling the speedratio of hydraulic couplings and change speed. gears.

The chief object of the invention is to automatically ctfect a change oftransmission ratio in such change speed gears so as to always maintainthe most suitable coupling.

The invention consists, primarily, in the speed ratio regulating meansfor hydraulic change speed gears being constructed and arranged in suchn'ianner that its controlling movements will be effected under theco1nbined influence both of the fluid pressure in the pressure chamberof the device and of the centrifugal force acting upon a rotatingmemher, so that the transmission ratios will be dependent on and changedwith both the turning moment of the driven member of the device (whichmoment is measured by the fluid pressure in the system) and the numberof revolutions per minute of the driving member. or the driven member,or both said mem-' bers.

A further object of the invention is to provide in a hydraulic couplingdevice one or more valves sensitive to the opposing actions ofcentrifugal force and fluid pressure, disposed so as to control the flowof fluid through a pump which is connected between driving and drivenelements, the position of said valve or valves thereby determining therelative/motion between said elements.

Further objects of the invention will be apparent from the detaileddescription of my invention with reference to the accompanying drawings.

In the drawings, several forms of a hydraulic coupling and change speedgear constructed according to the differential principle and speciallyadapted for automobiles or the like are illustrated as examples embodying the invention. Fig. 1 is a section of the one form of embodimenton the broken line 11 of Fig. 2. Fig. 2 is a section on line 2-2 ofFig. 1. Fig. 3 is an axial section of another form of embodiment. Fig. 4is a transverse sectional view of the delivery pump viewed from theleft-hand side of Fig. 1; Fig. 5 is a similar view of the firstreceiving pump to the left of Fig. 1, and Fig. 6 a similar view of thesecond receiving pump to the right of the first receiving pump. Fig. 7is an end view of the change speed gear viewed from the right hand sideof Fig. 1 and showing the ratchet device for checking the 575,673, andin Sweden November 16', 1921.

stator elements; Fig. 8 is a view similar to that of Fig. 2, showing amodification of the change speed gear wherein the control valves areactuated indirectly by centrifugal force; and Fig. 9 is a similar viewshowing a further modification wherein one of the control valves isactuated indirectly by centrifugal force and a spring and another of thecontrol said casing 2 is a driven shaft 3, such as the shaft of anautomobile, and keyed to the said shaft is a rotor 5 having radiallymovable vanes 4, said rotor 5 forming the driven rotor constituting, inconjunction with the driving rotor 2, the pump system normally operatingas a delivery pump. Placed in the casing 2 are, further, two mutuallyindependent stator pump elements 6 and 7 having radially movable vanes8, 9, respectively, said stator elements being keyed to sleeves 10, 11,respectively and adapted to be turned relatively to each other and tothe driven shaft 3. The stator elements 6, 7 with their vanes 8, 9 form,together with the driving rotor 2, the pump system normallv operating asreceiving pumps to receive the output of the delivery pump 2, 5. All thepump systems 2, 5, 2, 6 and 2, 7 are considered to be double acting, i.e. provided each with two diametrically disposed abutments and twoworking surfaces so that the device as a whole will be mechanicallybalanced. Attached to the free ends of the sleeves 10, 11 are pawls 12and 13 cooperating with ratchet teeth 14 in a frame 15 so that thestator elements 6 and 7 are free to rotate with and relative to thedriving rotor 2 when rotated in the direction of the arrow but areprevented from turning in the opposite direction. The pawls are actuatedby springs 61tending to retain the pawls in the position shown in Fig. 7and counteracted by centrifugal force exerted by the pawls when rotatingwith the stators 6 and 7 as is the case in direct drive, when bothreceiving pumps are cut out or when one of said pumps is cut out. Bysuch means the pawls 12 and 13 will, while rotatin and due tocentrifugal force,

' be held out 0 contact with the teeth 14 of the frame 15.

Placed between the pump system 2, 5 at one side and the pump systems 2,6 and 2; 7 at the other side is a partition wall 16 firmly connected tothe casing 2, said wall carry ing regulating devices arranged andoperat-. ing as hereinafter described. On accountp'f the arrangement ofeach pump element wlth two abutments, the regulatin devices are ar-.ranged in pairs at diametricall opposite points, one regulating device 0each pair only being shown in section in the figures, for the sake ofsimplicity.

iLlying in a plane perpendicular to the axis 0 t e transm1ss1on shaftsand from substantially diametrically opposite points on the pebores 17,18, 19forming cylindrical guides for the reciprocating piston valves 20,21, 22

All the valves are shown intheir outer posir tions in which the valvestem heads 26, 27,

28 placed at the inner ends of the valve stems 23, 24, 25 bear on theinner side of sleeves 29, 30, 31 which sleeves are rigidly attached tothe bores 17 18, 19 so as to prevent further outward movement of thevalves. Pivotally connected to the valve stem heads 26, 27, 28 areconnecting rods 32, 33, 3a pivoted to rings 35, 36, 37 respectively,which rings are adapted to 'turn independently on a drum 38 carried bythe partition 16. By such common mounting of corresponding-diametrically disposed valves-a like movement of the valves belongingto each pair is secured. llhe valve chambers or bores 17, 18 and 19 arepermanently connected at theirouter ends, throughthe openings 39 in thepartition 16 (Fig. 1), to-the pressure chambers of the pump system 2, 5,so that the valves 20, 21 are, directly actuated by the fluid pressurein the said chamber. In a certain predetermined position of the valves20, the valve chambers 17 will be connected through openings 40 (shownin Figs. 2, 5 and ,6) to the pressure chamber of the pump system 2, 6,

' so that a connection will be established between the pressure chambersof the pump systems 2, 5 and 2, 6. In a similar manner, through thevalve chambers 18 and openings 41 in the partition 16, the pressurechambers of the pump systems 2, 5 and 2, 7 can be connected. The valves20 and 21 actuated, during the operation of the change speed gear, bythe fluid pressure in the pump system 2,

t 5 will, further, be thrown outward by the centrifugal force, and theconnections between the pressure chambers of the pump systemshereinbefore described will, obvious- 1y, be established when the fluidpressure in the pump system 2, 5, and correspondingly the turning momenton the driven shaft 3, is

greater than the centrifugal force exerted by 1,701,9oa V the valvepistons 20, 21, i said {centrifugal force being dependent on the weightof the valve pistons and the number of revolutions of the-rotor 2 andthe-shaft 1.- As'shown in Fig. 2, the valve piston 20 is hollow whilethe valve piston 21 is solid, and, on account thereof, the'lighte'rvalve 20 will connect the pressure chambers of the pump systems 2, 5

and 2, 6v at-a less pressure than that at which 1 the heavier valve 21connects'the-pressure chambers of thepump systems2, 5 and 2, 7 .Theby-pass valves'22 actuated by centrifugal force and by springs 12 inopposite direcand thereby to gradually shut off the connection betweenthe pressure chambers of the pump system 2, 5 and the suction chambers,when the number of revolutionsapproach 300 per minute, at which speedthe'engine commences to develop useful power; The valves 21 are weightedand dimensioned so that, at a number of revolutions of, say, 900 perminute, ormore, and at a maximum turning moment of the driving motor,their centrifugal action exceeds the fluidpre'ssure then existing in thepump system 2, 5'so that the said valves begin to gradually shut oil theconnection between the pressure chambers of the riphery of the partition16 are parallel provide a condition of free engine in which 'the fluididly short-circuits from the pres and pump systems 2, 5 and. 2, '7.These valves will close gradually because of the fact that as they areprogressively closed, the ports 41 which they control are graduallyrestricted, this resulting in an increasein fluid pressure, which inturn increases-the resistance to further closing of the valve. Suchincreased resistance can only be overcome by a further 1 increase inspeed of the driving rotor. After valves 21 are fully closedand thespeed of the driving element further increased, valves 20 commence toclose, the outward movement of these valves in like manner graduallyrestricting portsiO until when suchports are fully closed, a directdrive is established, the fluid being then looked in the pressurechambers of the delivery pump 2, 5. As hereinbefore set forth, therelative timing. of the valves is determined by suitably proportioningtheir masses with respect to the'eflective pressure area of the valves.If the pressure areas are equal, as shownin Fig.2, the valves being ofthesame diameter, the action of the g valves is timed by providing adifferent mass for each, the valves 21 which are heavier being the firstto close.

Supposing the direction of running of the driving rotor 2 to be thatindicated by the arrow in Figs. 4, 5 and 6 and supposing further theopenings 40and 41, Fig. 2 (also 1ndicated for the sake of clearness bydashed and dotted lines in Figs. 5 and 6) to be shut by the valves 20and 21, a fluid pressure W111 arise in the chamber 51, Fig. 4, betweenthe abutments and the vanes 4, and the rotor 5 will be caused to rotatewith the same speed as does the driving rotor 2, it being assumed thatthe valves 22 shut off the connections 43 between the pressure chambersand the suction chambers of the delivery pump 2, 5. The pressure fluidin the chambers 51 enters through the openings 39 to the valve chambers17 and 18, F ig. 2, at the outer ends of the control valves 20 and 21,which will, thus, be exposed to the said. fluid pressure.

If then the load to be driven increases, also the fluid pressure willincrease and at a certain relationship between said pressure and thecentrifugal force exerted for instance by the valves 20, said valveswill be moved inward and open the ports 40, Figs. 2 and 5, leading tochannels 52, Fig.5, which are open to the chambers 53 between the oneside of the abutments 46 and the vanes 8 of the first receiving pump 2,6. Due to the pawl and ratchet device 13, 14, Figs. 1 and 7, the stator6 with its vanes 8 cannot turn in a direction opposite to that of thedriving rotor and, consequently, a fluid pressure will arise in the saidchambers 53 causing a reaction 'force on the abut-merits 46, which willbe transmitted through the rotor body 2 to the abutments 45 of thedelivery pump 2, 5 and from there through the fluid to the driven rotor5. Thus,

the torque of said latter rotor 5 avill increase correspondingly and atthe same time the rotor 5 will slip with relation to the driving rotor 2or obtain a decreased speed of rotation, which is dependent on therelation between the volumetric capacities of the delivery pump 2, 5 andthe receiving pump 2, 6. The fluid delivered to-the receiving pump 2, 6is withdrawn through the openings 54 at the opposite sides of theabutments 46 and led to the annular suction chambers 55, whichcommunicate through openings 56, Fig. 4

with the suction chambers 57 of the delivery pump 2, 5. Thus, acirculation of fluid takes place between the delivery pump 2, 5 and thereceiving pump 2,6.

Further, if the load to be driven be still increased, the speed of thedriving rotor 2 remaining constant, also the fluid pressure increasesand the valves 21 are caused to open the ports 41, Figs. 1, 2 and 6, andestablish a communication between the pressure chamr bers 51 of thedelivery pump 2, 5 and the pressure chambers 58 of the second receiving6, a fluid pressure will now arise also in the chambers 58 and cause areaction force on the abutments 47, which is, as before, trans mitted tothe driven rotor 5, the slip of which relatively to the driving rotor 2will be further increased at the same time as its tor ue will increasecorrespondingly. The fluid elivered to the receiving pump 2, 7 isreturned through the openings 60 at the opposite sides of the abutnients47, the annular chambers 55 and the openings 56, Fig. 4, to the suctionchambers 57 of the delivery pump 2, 5.

It will be understood that the transition between successive stages ofcoupling, as hereinbcfore set forth, occurs without shock inasmuch asthe movement of the valves is smooth and gradual. During the periodsthat the valves are in motion asli ping clutch effect is an inherentcharacteristic of the transmission, and this is true of-each of thethree sets of valves. In shifting from neutral through the severalstages to direct drive, it will be seen that the gradual closure ofvalves 22 finally results in a positive fluid drive at the ratiodetermined by the relative volumetric capacities of the cooperatingpumps. Thereafter the gradual closing of valves 21 results in a smoothtransition from the first speed ratio to the second speed ratio' whichis determined by the relative capacities of pumps 2, 5,2, 7. The sameaction will occur during the closure of valves 20 during which thetransmission ratio is shifted from second speed to direct drive. Duringthe aforesaid transition periods, until the particular pair of valveswhich tive under given conditions of fluid pressure and centrifugalforce, has opened sufiiciently 'to pass fluid substantially without anyobstruction in quantities sufficient to meet the demands of thereceiving pump or pumps which at that time may be cooperating with thedelivery pump 2, tion is taking place. The resistance which the valvesin any partially closed position offer to the flow of fluid, results ina direct application of torque between the driving rotor 2 and thedriven rotor 5, because of the fluid pressure developed from the partialclosure of such valves. This slipping clutch action will decrease untilwhen a particular setof valves is closed, a positive coupling isprovided atthe next higher transmission ratio.

It will be understood that the action of valve springs 42 is soproportioned with respect to the centrifugal mass of by-pass valves 22that said valves will occupy a wide open position (a radially inwardposition) whenever the speed of the driving rotor is remay be opera- 5,a slip'plng clutch accrease in speed, or decrease h the motor accordingto the speed duced below 300 R. P. M., for example, or

such other speed as may be found satisfactory for the idling speed ofthe engine when the transmission is in neutral. With the said valvesfully open, no appreciable pressure willbc developed in the chambers ofthe dclivery pump 2, 5, and the transmission will be set in neutral.lhis automatic declutching action positively insures against stallingthe engine in a motor vehicle for example, the clutch always disengagingbefore the engine is slowed down to a stalling speed.

In accelerating. the operation is just the reverse of that above' setforth. The coupling starts in neutral, valves 22 gradually closing andthus progressively reducing the slip between the driving and drivenelements.

For a certain period afterthe closure of valve 22, valves 17 and 18remain open, permitting both the receiving pumps tocoact with thedelivery pump ,to establish the first speed driving ratio determined bythe relative capacity of the pumps.

in fluid .pressure, the valves 21 will gradually close, thus cutting outthe receiving pump gradually est blishing the second speed drivingratio. Upon a still further increase in speed or decrease in load thevalves 20 will commence to close, thereby by gradual stages shiftingfrom second speed to direct drive. From the foregoing it will be clearthat each pair, of valves during successive transition periods underconditions resulting in changes in driving ratio toward direct drivevirtually provides a smooth and gradually increasing clutching efiectfor the transmission stage of next higher ratio, the reverse operationoccurring in shifting from direct drive through the several stages toneutral.

It will be clear from the aforesaid-that the transmission ratio will beentirely automatically regulated in accordance with the actualcircumstances, being controlled both by the load on the driven shaft andthe R. P. M. of

the driving shaft. The'operator is thus required merely to control thefuel su ply to at w ich he desires to travel. I

The form'of embodiment shown in Fig. 3 difi'ers from that previouslydescribed in that the driving shaft 1 is connected. directly to the,rotor 5, which thus becomes the driving instead ofthe' driven rotor,and the driven shaft 3 is firmly connected, through the par tition wall16, to the casing 2 which will thus form the driven rotor instead ofthedriving one. The valves (only 21visible in Fig. 3) also here areplaced in the partition'wall 16 of the casing 2 and actuated, as before,by

. the pressure 1n the pump system 2, 5, but their action will now bedependent on the number of revolutions-of the driven member (casing 2with shaft 3) instead of by the-number of Upon a further ini 2, 7, andthereby menace revolutions of the driving member (casing'2 with Shaft? 1l The -modification shown in Fig. 8 difiers from that shown in Fig. 2 inthat the valves 20 and 21' are actuated indirectly by centrifugal forceby means of radially slidable weights 62 and 63 connec'ted'b means of:

weights 62 and, thus, assisting the fluid pressure indirectly, while-thevalves 21 are actuateddlrectly bysprings 67 counteracting the fluidpressure and assisting the centrifugal force of the weights 63indirectly.

It IS obvious that the conditions may be varied by suit-abl changing thevalve systems which may e actuated, if desired, by sprmgs orthe likesupporting or counteractmg the centrifugal force,-or the fluid pressure,respectively. Moreover, the valve systems need not be directly operatedby the centrifugal force and the fluid; pressure, as sho n, but, ifdesired, the said powers may act on the valve systems through suitabletranslations.

Also in other respects, the invention is not limited to the embodimentsof hydraulic couphng and change speed gears shown in the drawings butmay be employed even in cases .where there are two pump. systems only,or

more than three.

ll claim: 1 l. A hydrauliccoupling and changesp'eed gear, comprising adelivery pump and at least one receiving pump, and valve 1 controlledcounteracting the centrifugal force of the Mil) force, so as to open andclose said passages respectively, in accordance with the fluid pressureset up in the delivery pump in overcoming the load tobe driven and inaccordance with the speed of one of the rotating members of the changespeedgear.

3. A hydraulic coupling and change speed gear, comprising a deliverypump and at least one receiving pump, and valve controlled passagesbetween said delivery pump and said receiving pump, means adapted tocontrol said passages, said means being movably carried by a rotatingmember of the change speed gear and adapted to be moved in a directionto open said passages by the fluid pressure set up in said delivery pumpin overcoming the load to be driven and being adapted to be moved in a.direction to close said passages by the centrifugal force due to therotation of said rotating member, whereby the position of said controlmeans will be determined by the resultant force of the aforesaid opposedforces.

4. A hydraulic coupling and change speed gear, comprising a delivery pumand a plurality of receiving pumps, an valve controlled passages betweensaid delivery pump and said receiving pumps, a plurality of meansadapted to control said passages, said means being movably carried by arotating member of the change speed gear and adapted to be moved in adirection to close said passages by centrifugal force due to therotation of said member and to be moved in a direction to open saidpassages by fluid pressure in the delivery pump due to overcoming thetransmission load and each of said means having a dificrent ratiobetween its susceptibility to centrifugal actuating force and its activearea exposed to fluid pressure whereby at increasing engine speed, thetorque load remaining constant, the several control means will act in' apredetermined series to vary the quantity of fluid delivered by saiddelivery pump.

5. A hydraulic coupling and change speed gear, comprising a deliverypump and a plurality of receiving pumps, and valve controlled passagesbetween said delivery pump and said receiving pumps, a plurality ofmeans adapted to control said passages, said means being movably carriedby a rotating member of the change speed gear and adopted to be moved ina direction to close said passages by centrifugal force due to therotation of said member and to be moved in a direction to open saidpassages by fluid pressure in the delivery pump due to overcoming thetransmission load and each of said means having a different ratiobetween its centrifugally active mass and its active fluid pressuresurface whereby at increasing torque loads, the engine speed remainingconstant, the several control means will act in a predetermined seriesto permit an increasing quantity of fluid to be delivered by saiddelivery pump.

6. A hydraulic coupling and change speed gear according to claim 1,including an auxiliary spring fluid control means adapted to be actuatedby centrifugal force in accordance with engine speed whereby until theen- .gine; has reached a certain predetermined speed, free egress of thefluid from id pump will be aflorded regardless of any load on thetransmission.

7. A hydraulic coupling and change speed gear according to claim 1, inwhich said delivery pump and said receiving pump or pumps are formed ,bya rotary driving member, a rotary driven member and at least onenormally stationary member, one of said rotary members being common toboth the delivery pump and the receiving pump or pumps, said controlmeans being carried by said common rotary member. s

8. A hydraulic coupling and change speed gear according to claim 1, inwhich said delivery pump and said receiving pump or pumps are formed bya rotary driving member, a rotary driven member and at least onenormally stationary member, said rotary driven member being common toboth the delivery pump and the receiving pump or pumps, the meanscontrolling the connections between said deliver and receiving pumpsIlgeing carried by sai common driven mem- 9. A hydraulic coupling andchange speed gear, comprising a delivery pump and one or more receivingpumps and communications between said delivery pump and said receivingpump or pumps, means adapted to automatically controlsaidcommunications, said means comprising substantially radially movablepiston valve members mounted in a partition between said delivery pumpand said receiving pump or pumps and exposed at their outer ends tofluid pressure set up in the delivery pump to open said communicationsand having its centrifugally active mass proportioned with respect toits active fluid pressure area so as to close said communications at apredetermined speed of rotation of the member carrying said partitionand at a predetermined fluid pressure set up in said delivery pump.

' 10. A hydraulic coupling mechanism with which to connect a drivingelement with a driven element, said mechanism comprising a fluid pumpconnected between and actuated in accordance with the difl'erence inspeed between said elements, a passage connecting the intake and exhaustsides of said pump, a valve in said passage adapted to control anddominating the circulation of fluid through said pump and thereby tocontrol the relative movement between said elements, and an automaticvalve control comprising centrifugal means sensitive to the speed of thedriving element, said means tending to close said valve, and pressuresensitive means tending to open said valve, said two means actingoppositely upon the valve to cause a substantial reduction in therelative speed between the driving and driven elements upon a maancewith the resultant force of the opposing actions ofcentrifugal means andfluid pressure, t e said valve means being sensitive in the oniedirection to centrifugal force due to the speed of'the driving element,and in the opposite direction to the fluid pressure gener ated by thepump, increments in fluid pressure when the speed is constant adjusting,the

valve means to increase the flow of fluid through said passage, andincrements in the speed ofthe/ driving element when the pressure isconstant adjusting the valve means to decrease theflowof fluid throughsaid passage. Y 12. Ahydrauliccoupling mechanism with which to connect(a driving element with a driven element,- said mechanism comprising apump connected between and actuated in accordance with .the diflerencein speed of said elements, a valve adapted to control and dominating thefiow of fluid from said pump, centrifugal means controlled by the speedof the driving element tending to close said valve andpressure-sensitive means tending to open said valve, the position of thevalve and consequently the flow of fluid from said pump beingsubstantially determined by the resultant .ofthe said opposing forces ofcentrifugal action and fluid pressure.

13. A hydraulic coupling mechanism with q aromas which to connect adriving element with a driven element, said mechanism comprising a fluidpump connected between and actuated in accordance with the diflerence inspeed between said elements, and means sensitive to the opposing actionsof centrifugal force and fluid pressure adapted to control anddominating the flow of fluid through said .pump in accordance with theresultant of said opposing actions, the relative motion between thedriving and driven elements being substantially inversely proportionalto the centrifugal force under conditions of uniform pressure and beingsubstantially proportional to the fluid pressure under uniformconditions of centrifugal action.

1a. A hydraulic coupling mechanism with which to connect a driving shaftwith a driven shaft, the slip of said mechanism being controlled by theflow of a fluid, said mechanism comprising a valve arranged to receivepressure from the fluid tending'to open the valve, together withcentrifugally-operated means tending to close the valve, said valve thedriven, shaft, a valve adapted to control and dominating such flow ofsaid fluid, said dominating valve beingarranged and adapted to be actedupon oppositely by centrifugal force tending to close it, and by thepressure of said fluid tending to open it, the slip of the couplingvarying directly with the load and inversely with the speed.

In testimony whereofl have signed-my name.

SVEN GUSTAF WINGQUIST.

